Patient-reported Quality of Life in Patients with Primary Metastatic Prostate Cancer Treated with Androgen Deprivation Therapy with and Without Concurrent Radiation Therapy to the Prostate in a Prospective Randomised Clinical Trial; Data from the HORRAD Trial

Background: A survival benefit was demonstrated for patients with low-volume metastatic prostate cancer (mPCa) when local radiotherapy was added to androgen deprivation therapy (ADT). Objective: To determine the effect of ADT combined with external beam radiotherapy (EBRT) to the prostate on health-related quality of life (HRQoL) of patients with primary bone mPCa. Design, setting, and participants: The HORRAD trial is a multicentre randomised controlled trial recruiting 432patients with primary bone mPCa between 2004 and 2014. Intervention: Patients were randomised to ADT with EBRT or to ADT alone. Outcome measurements and statistical analysis: Patients completed two validated HRQoL questionnaires (European Organization for Research and Treatment of Cancer [EORTC] Quality of Life Questionnaire Core Module (QLQ-C30) and EORTC Quality of Life Questionnaire Prostate Module [QLQ-PR25]) at baseline and at 3, 6, 12, and24 mo after the initiation of treatment. The effect of both treatments was evaluated based on mixed-effect models. Results and limitations: Patient characteristics and HRQoL scores at baseline were similar in both arms. At baseline, 98% of patients completed the questionnaires, compared with 58% at 24 mo. Patients reported significantly more diarrhoea (difference between the groups 10.8; 95% confidence interval [CI] 7.3–14.2), bowel symptoms (4.5; 95% CI 2.1–6.8), and urinary symptoms (11.9; 95% CI 8.9–14.8) after EBRT and ADT compared with ADT alone (all between-arm difference p < 0.001). Urinary complaints levelled at 6 mo. At 2 yr, only bowel symptom scores were significantly different (8.0; 95% CI 4.8–11.1, p ≤ 0.001), but 68% of patients in the radiotherapy group did not report clinically relevant worsening of their bowel symptom scores. Conclusions: Patients with bone mPCa reported temporary modest urinary and bowel symptoms after combined treatment with EBRT of the prostate and ADT compared with ADT alone. For some patients (22%), deterioration of bowel functions remains at 2 yr, whereas general HRQoL does not deteriorate. Patient summary: This study investigated the effect of radiotherapy to the prostate added to hormonal therapy on patient-reported health-related quality of life (HRQoL) in patients with primary bone metastatic prostate cancer. Most patients reported only temporary urinary and bowel symptoms. In 22% of patients, bowel symptoms remained at 2 yr, whereas general HRQoL did not deteriorate. Patients with bone metastatic prostate cancer reported temporary modest urinary and bowel symptoms after combined treatment with prostate radiotherapy and hormonal therapy compared with hormonal therapy alone. Both treatments did not affect global health-related quality of life.